During operation of a gas turbine engine, pressurized air from a compressor flows into a head end volume defined within the combustor. The pressurized air flows from the head end volume into an inlet to a corresponding premix passage of a respective fuel nozzle. Fuel is injected into the flow of pressurized air within the premix passage where it mixes with the pressurized air so as to provide a fuel and air mixture to a combustion zone or chamber defined downstream from the fuel nozzle. The flow of pressurized air is typically non-uniform as it approaches the inlet to the respective fuel nozzle which may be undesirable for efficient combustor operations.